Automatic-telephone substation mechanism.



A. E. STEVENS.

AUTOMATIC TELEPHONE SUBSIATION MECHANISM.

APPLICATION HLEO APR. 2|. 191..

Patented Sept. 24, 1918.

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In I; e nior 31M ALE. STEVENS.

AUTOMATIC TELEPHONE SUBSTA TION MECHANISM. APPLICATION man APR. 2:. Ian.

Patented S t. 24, 1918.1 I

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In v 62 72 2021: .4. m1 z m AZiorney.

A. E. STEVENS.

AUTOMATIC YELEPHONE SUBSTATJON MECHANISM. APPLICATION FILED APR. 21.Hill- PatentedSept. 24,

Lngvefiior:

. A. E. STEVENS;

AUTOMATIC TELEPHONE SUBSTATIUN MECHANISM.

1 280,091 Patented Sept. 24,1918.

5 SHEETS-SHEET 4.

APPLICATION FILED APR. 2!. 19]]- fnv era/Z07 i AZiorney.

A. E. STEVENS.

AUTOMATIC TELEPHONE SUBSTATION MECHANISM.

Pienmd Sept 24,191

APPLICATLON FILED APR. 21. Hill- Eur/0N3 therein Third, in means w cever is removed from its connected mechanism UNITED STATES PATENT oFFIoE.

ALTON E. STEVENS, 0F PROVIDENCE, RHODE ISLAND.

AUTOMATIC-TELEPHONE SUBSTATION MECHANISM.

To all whom it may concern:

Be it known that I, ALTON E. Srnvaus, a citizen of the United States,residing at Providence,in the county of Providence and State of RhodeIsland, have invented certain new and useful Automatic-TelephoneSubstation Mechanism, of which the following is a specification,reference being had to the accompanying drawing.

My invention relates to means employed at the calling station of anautomatic telephone system, for selecting, signaling, communicating witha called statlon, and particularly when said means are mounted in a unitembracing the telephone transmitter and receiver.

My general purposes. are to reduce to a minimum, the manual movementsrequired in makin telephone connection to a desired statlonj tocompelthe operator to use the apparatus in the way intended; and to preventany tam ering on his part, from mterfering'with t e'successfuloperations of the apparatus.

The various features of said invention may be said to'reside, first, inmeans where- 'by the rotatable selecting dial of a telephone stationmay, without injury to the mechanism, be manually moved beyond theposition required for calling an desired station, and then back to, anleft in, said position. 1

Second, in means for governing the speed of the return of said dial andconnected mechanism, to normal position.

hereby when the rehook, the dial and any forward manual movement, untilthe receiver is placed upon its book.

Fourth, .in means whereby when the re- I ceiver is removedfromitshookswitch, the

dial and connected mechanism,

will automatically return to normal position and in so.doing will sendthe desiredselecting, and the'ringin impulses required in communicatinwiti it called stat on.

Fi th, in means for operating contact springs to cause an automatic sinle signal at the called station; and for ren ering the manual rin ingcircuit operat ve upon the returnof the mechanism to normal position.

Sixth, in means whereby-the ringing circuit of a manually operatedringing button,

Specification of Letters Patent.

become locked against Patented Sept. 24, 1918.

Application filed April 21, 1917. Serial No. 163,580.

maybe held open while the impulse transmlttmg mechanism is out of normalpositron.

Seventh, in various other particular forms (tembodying the broadfeatures of my inven- My invention is designed rimarily to operate withan automatic te cphone system, more fully described and claimed in myapplication for Letters Patent, No. 72, i28, filed January 17, 1916, butits use is not neces sarily limited to that system.

In the drawings illustrating the )rinciple of my invention and the bestin e now known to me of embodying the same in 0perat ve structure,

F 1 ure 1 represents a side elevation of a telep lone statlon;

Fig. 2 represents a front view of the same, partially broken away andshowing the sending dial;

Fig. 3 is a side elevation of the base of the station, shown in Fig. 1,with the casing cut awa to show mechanism within;

F1 4C is a bottom view of what is shown in Fig. 3; 1

Fig. 5 is a cross section of the base of Fig. 1;

Fig. 11 is a diagrammatic .view of wiring and apparatus employed by acalling and a called station making use of my invention, and, exceptingthat it is more specific as to some details, is substantially the sameas so much as corresponds and is shown in' the drawings of my saidpending ap. lication..

Other features, indicated in Fig. 1 but not described and claimedherein, are described .and claimed in application, Serial No.

165,126, for automatic telephone central station apparatus, filed byme-April 28 1917-.

A station mayconsist of a base 1, Figs. 1 and2, and standard 2, and atransmitter 3, and a receiver 4, all of the usual commercial type.Onthebase 1 is mounted what'may 'lhc spring it being adapted to contact.

be called the sending mechanism 5, showin externally a knob (5 attachedto a dial which is fixed to a shaft .8, Figs. 3 and 4, and which may bemanually moved under a stationary indicator-hand 9, by means of the knob6. Upon this dial are arranged letters or mnnbers, say 1-30 which, inconnection with the indicator, show when the apparatus has been manuallymoved to the proper point to allow the system to establish connectionwith the party desired. The knob and shaft tend to return to theirnormal position by the action of a flat coil spring 10, Fig. 8, in thespace underneath the dial 7.

Mounted loosely on the shaft 8 is a small pinion 11, Fig. 6, which bymeans of a pawl 12 pivoted to a centrifugal governor 13, drives thegovernor, thereby controlling the speed of the device, while returningto normal position. This oovcrnor also is loosely mounted on the shaft8, Fig. 9, and consists of small weights 16 attached to one end of brakelevers l7, pivotally mounted at points 18 on the frame of the governor.The outer extremity of the levers are turned up to form brake shoes 19which are pressed against the circumference ofa drum 1%, as the weights16 are moved out by centrifugal force; the drum 14, being attached tothe frame 15, Fig. (i of the sending device.

A driving gear 20, Fig. 3, fixed to the shaft 8, drives an impulse gearwheel 21, on shaft 8', Figs. 7 and 10, through a pinion 22 fastened toits under side. The under surface of the impulse wheel has impulsepoints or projections 23, Figs- 7 and 10, to close a selecting circuit;and also has near the circumference, a ratchet 24.

In. an extension 25, Fig. 6, of the base of the frame 15, is mounted ashaft 26, secured to the top of which is an arm .27, Fig. 7. This armcarries at each end, pawls 2S and .29, Fig. 10, the pawl 28 engaging,and being held in engagement with, the teeth on the impulse wheel 21, byasprin '30, Fig. 6; while the pawl 29, Fig. 10, is being held in contactwith the teeth 24 on the circumference of t-lieimpulsc wheehby a smallspring 300, Fi 10. Secured to the lower portion of the shaft 26, aretwo'arms' 2-31 and 32, V- shapccL-one 31 carrying a vertically extendedam 33; to the other 32, llicrc is attached a small spring SH lixed'tothe frame...

Mounted on aislub 35. Figpti. and fastened to the frame, are two contactsprings 36 and 37. the upper spring having an upwardl extending V-shapcdbcud 13S. resting on the under surface of the impulse wheel 21 in theline of the impulse projccl ions 2 l'pon the same stub are three othercontact .springs- 39, 10 and ll. Fig. 8; the spring 39 being adapted tobe moved into coulact with the spring It) by means of a projection I20on the upper face of the driving gear 20: and and remain in contactwith, said projection when'tlie driving gear returns to normal position.

Electric current is conveyed to these sev-. eral contact springs bywires leading to the fixed contact: or jack springs 42, 43, 44, and 45,Figs. 6, 7 and 1.1, which are mounted upon the dial frame, and insulatedtherefrom. 'hen the dial unit is inserted in the .standard, thesesprings contact similar springs it), 4.7, 18, and 49, Fig. it, fixed ininsulating material in the standard,,thus eti'ecting a junction betweenthe wiring of the unit and of the telephone station.

It should be noted that. all the mechanism just described is mountedupon, and contained in, the frame 15 of the sending device 5, which isreadily removed from, and replaced in. the base 1 of the sendingstation, shown in Fig. 1; a screw (32, Fig. 1, holding the device in thebase.

receiver hook 50, Fig. 2, of the usual pattern is pivoted in thestandard 2 of the station t. any convenient point. 51. Attached to thisand adapted to be moved vertically, is a connecting rod 52, havinglimited motion, and being held normally at the top of its stroke, whenthe receiver is removed from the book, by means of a coil spring 53,Fig. 3. This connecting rod 5.2 engages, at its bottom, with an anglearm 51, pivoted at a central point 55, and held in contact with theconnecting rod 52, by means of a small spiral spring 56. The otherextremity 57 of this angle arm engages and disengages with the cam 33 onthe extremity of the arm 31, whereby a slight degree of motion is givento the extremity of the angle arm 27. The angle arm 5; carries on itsunder side, an insulated boss 58 resting upon the main ontact spring 59,Fig. 5, one of the conventional hook contact springs mounted upon a stub(30 attached to the frame of the base; the main spring 59 being moved bythe boss 58 on the end .of the angle arm 54.

A push-button 66, Fig. 5, of the usual form, is mounted on one side ofthe base 1, and moves the contact springs 67, ()8, and (it), which aremounted in the frame on the stub 70. e.

2 is also fixed in the base lv advantages of my construction will beperceived.

Having now briefly described the preferred form of construction of mytelephone station, I will now describe its operation.

Let us suppose that a person at station 3, Fig. ll, desires to callstation 4. The knob 6, Fig. 2, and dial 7 are turned for ward-until thefixed indicator 9 points to the desired station '4, on the dial; butsimultaneously, the impulse wheel 21 also turns, allowing four teeth inthe ratchet 24.. Figs. 6 and 7, to pass the pawl :28, which is heldagainst the ratchet by the arms :27 and 32, and spring 34. By means ofthis pawl, the sending device 5 is held from the normal position, towhich it tends to return by the j action of coil spring 10, Fig. 8. If,for any reason, the dial 7 is manually moved ahead of the characterindicating the desired station, the dial may be moved back to theposition required; for the reason that the nut] 28 and its controllerspring so. ig. 6, lieing of such form and strength that, by th use. ofsuliieient manual force. the teeth of the rack 24 will overcome thespring 30, and pass by the point of the pawl. Thus the first feature ofmy invention attains its object.

Next, the. receiver 4 is removed from its hook 50, which is lifted bythe action of the spring 53 on the connecting rod 51!. As the connectingrod rises, the spring 56 on the pivot causes the angle arm to move. whenthe pressure of the connecting rod. on its inner extremity, is released.The other extremity 57 of the un le arm isthcn bron ht C I: t

in contact; with the Etlnt 33. turning the shaft ZGsIight-ly. As theshaft :26 turns. it moves the arm :27 away from the circumfercm'c of theimpulscwheel 21, causing the pawl 28 to disengage the ratchet 24.

The spring 19 driving the shaft 8. is now free to rotate the shaft 8 andthe impulse wheel it, to its normal position, the speed of returnf'being controlled by the pressure oflhe brake shoes 19 of the governor,on the drum 14. This explains the second fca- As the shaft 26 moves the.pawl 28 from engagement, it causes the pawl 29, Fig. 10, on the otherextremity of the. angle arm :27, to engage the teeth in thecircumference of the impulse. wheel 21, and allows no motion of theimpulse wheel, except that returning it.to normal position. The thirdfeature is now plain.

\Vliilc the impulse wheel 21 is returning to normalv position, fourimpulse. projections 23. Figs. ti, 7, 10, and .11, pass the V-shapedbend in the spring 36, causing the spring 36 to contact four-times withspring 37. thus closing the selecting circuit to central station, fourtimes. When, in setting the device, the impulse wheel 21 was turned bythe knob 6 amt shaft 8, the driving wheel 20 was also revolved aproportionate part of a revolution. While the system is returning to.normal, the projection 420 on the upper surface of the driving wheel 20is, after the selecting impulses have been sent, but before the drivingwheel reaches ncrmal position, brought into contact with the calm likeprojection on the extremity of the spring 39, causing it to make andbreak contact once with the spring l0. This causes current to be sentthrough the bells at the called station, automatically operating themwithout further etl'ort. on the part of the operator of the callingstat-ion. The fourth feature of my invention becomes clear.

But after the projection 420 on the driving wheel '20, has passed'theringing springs, it contacts. and remains in contact with, the springll, the driving wheel having returned to normal position and stopped.This renders operative the manually opcrated ringing circuit, which maybe operated when the sending apparatus returns to normal. .Vhile thisapparatus is out of normal, the ringing circuit interrupted, and hencecannot be operated. This explains the operation of the fifth and sixthfeatures of my invention.

To show how the various features of my invention at the sending station,as 3, are combined in an automatic telephone system, I will refer todiagrammatic view Fig. 11, and describe the electric circuits employed,and apparatus operated, in callingany particular station.

The party at station 3, wishing to talk with person at station 4, asalready stated, has turned the knob and the impulse wheel .21 in aclockwise direction to the point marked 4, the. spring arm holding theimpulse. wheel in position. Upon the removal of the receiver t from thehook 50, the spring arm becomes disengaged from the impulse wheel 21,and permits it to return to normal position, under tension of thespring. \Vhile the impulse wheel 21 is returning, the projections 23-cause the spring 36 to make contact. with spring 37. four times, therebyclosing a selecting circuit fromground 85, through springs 86 and 87,which came into contact upon the removal of the receiver, through wire88, springs 36 and 37, wire 89, selecting magnet 90, to battery 91. Theselecting magnet 90 is tbcreb y energized four times. and attracts itsselecting armature 92, causing the stepping pawl 93 connected therewith,to engage four teeth in succession, in the ratchet wheel 94, therebystepping the brush Sta-to fourth contactpoint 96, in the contact bank97, which contact point is conncctcd bank wire 98, to the. selector andtelephone of station 4.

At the first step from normal position of the ratchet wheel 9-1, theholding detent H0 is caused to engage the teeth in said ratchet, andhold it at each successive step in the tol lowing manner: As saidratchet wheel lirst; mores from normal position, it's arm 95) hasdisengaged the spring switch 100, thereby permitting it to make contactwith spring 101, establishing a holding circuit through the holdingmagnet as follows:lrom ground H3, through battery tll, nmgnet 103,springs 101 and 100. wires 10 imluction coil T1, transmitter 23, springsHT and $6 to ground 85. This causes the holding magnet; 102 to beenergized, and attract its holding armature 103 thereby permittingdetent Ht) to engage the ratchet wheel by the pressure of small springlot. This holding armature I rarries an extension which engages aninsulated extension it)? on a switch 108. The, tension of the spring141, however, is so great that the amount ol current flowing tlirrz-ughthe. coils of the magnet 102, is not ullieient to energize the magnetsullieiimt'ly to allow the armature .ltJJ to more the switch l out ofcontact with the point. 10-). \Vliile the springs 36 and 37 are incontact for the last of the series of selecting impulses, the projection120 on the driving wheel 20, causes the ringing spring 59 to makecontact with the spring 40, thereby short-circuiting the transmitter 3and induction coil Tl, and by reducing the resistance in the holdingcircuit, causing an additional amount ofcurrent to flow through thecoils of the holding magnet 102, thereby increasing its energy to such adegree as to cause the lmlding armature 105 to overcome the tension ofthe spring 111. and make contact simultaneously with the springs 105)and 110. The contact between the. pi'i 119 and 40 being broken when theimpulse wheel 21 comes to rest at. its normal position, the transmitter23 and induction coil 71, are again brought into circuit with the coilsof magnet; 102, and the amount of current flowing in this holdingcircuit is decreased. This current, however, is sutlicient to cause. then'iagnet 10; to hold the armature 10 after it; has once been attracted.

The contact between springs 39 and 40, made as just deseribeil,mnnpletes a ringing circuit, whereby the ringer 11l, atstation 4, isoperated, this ringing circuit being as 'sllnz'is. l-rom the ground 85,through springs Hth HT. driyfing wheel 20, projection 1-20. springs t!)and 40, wires 103 and 112, sprin 's 112-1 and 114-, 115, 108, and 110,to brush .1? which is in contact with the. point; 1H3, bank wire. 98 andwire lltl of station 1, the springs HT and N8, the. wires H9 and 1:20,the ringer 111. the springs lll and i212, the wire 12 the selectingmagnet 121, but.- tery 91 and ground no.

The ringer 111 is ol' high resistance, amt tlnrselecting magnetlIZl isof low resistance,

this latter being, adjusted so that it will independently not operatethrough the resistance of the ringer.

The party at station t, upon receiving his signal. remores the receiver125 from the hook 12th and can now communicate with the party at callingstation 3, over the following talking eircnit:----lrom the ground Hthrough springs H6 and ST, transmitter t5, induction coil 71. the wires103 and 112, springs 1-13 aml 1H, springs 115, 108, and Ill) to thebrush U5 and contact point; 96, bank wire 9h. wire 11(3, springs 117 and118, wires 11!) and 120, induction coil 142. transmitter 12?. wire 12S,springs 131 and 130, to ground 85; the springs 130 and 131 being broughtin contact with each other, upon the removal of the. receiver 1'25 fromthe hook lL 'rwhich is drawn up by the spring 1130.

liatlery power is supplied to energizev the. transmitters and receiversat. each station as; follows: From ground H battery Ul, through magnet 12. springs lbl and i 'l wire 1H2} to station t; aml o\'er the wire 1 tto station l, by a duplicate circuit Stat ions '1 and -I- havinglinished comn'iunication, the connection is discontinued by placing thereceiver l, on the hook it) thereby breaking connection between springs86 amt 87, causing the holdingmagnet 102 to become dei nergixedwhereuj'mn its armature N13 is released. and causes the detent lit) todisengage the ratchet wheel il. 'lhis ratchet wheel, upon beingreleased, returned to its normal position, as shown in the drawings byan suitable spring. If the called party does notv respond. the calling,party, the receiver i being oll' its hook 0, may manually eiill him bypressing a button as, which makes a circuit between springs t3? and(it); the receiver 4 and transmitter 3 being short-circliited; themanual circuit being from ground 85, springs 86 and 37, wire 88, drivingwheel :0. projection 1:20, spring 4L springs t3!) and ($7, and the ringing circuit already deseribetl.

Should the button t'ili be pressed while the sending apparatus is out ofnormal position, the, circuit. would not thereby be. eonipletei l, forthe circuit to ground, would be. broken between the projection 420 onthe driving wheel '30. and the spring ll.

ln eonelusion, the particular sending mechanism here. shown is thatactually used at each calling and called station o't'tho system showndiagrammatically in Fig. 11, and disclosed andclaimed in my said pendingapplication.

Desiring to protect my invention in the broadest manner legallypossible,

What l claim.

l. i\ rotatable call dial; selecting illlpulSc mechanism prorided with aratchetwheel; a springeol'itrolled arm, and a spring controlled pawlpivoted thereto, and in engagement with said 'atehet wheel; all arrangedto allow the dial. to be manually moved forward oi" back and retained inthe position where. llltllllltllll' ltlfli, to facilitate thepositioning the dial; a receiver switch; a re eeiver removahly mountedthereon; means connecting said switch, with said spring eol'itrolledarm, whereby a removal of the receiver from its switch, permits thelatter, through said means, to operate said arm and move saidspring'controlled pawl to disengage said ratchet wheel and allow saidselecting impulses to be transmitted.

2. A rotatable call dial; selecting impulse mechanism provided with aratchet wheel; a spring eontrolled arm, and a spring controlled pawlpivoted thereto, and in engagement with said. ratchet wheel; allarranged to allow the dial to be manually moved forward or baelt andretained in the position where manuall v left, to facilitate inpositioning the dial; a spring controlled lock pawl pivoted to a secondarm il'itegral with the first, and designed to be moved into engagementwith said ratchet wheel when the latter has become disei'igaged by thefirst spring controlltul pawl, to prevent a movement other than towardnormal osition 3. A rotatable call dial; selecting impulsemechanismprovided with a ratchet. wheel; a spring controlled arm, and asoring con trolled pawl pivoted thereto, and in en agement with saidratchet wheel: all arranged to allow the dial to be manually movedforward or back and retained in the position where manually left, tofacilitate positioning the dial; a spring controlled lock pawl pivotedto the said arm, and designed to he moved into engagement with saidratchet wheel when the latter 'has become disengaged by the first springcontrolled pawl; a receiver switch; a receiver remorably mountedthereon; means connecting said switch with said spring controlled arm,whereby a removal of the receiver from its switch, permits the latter,through said means to operate said arm, and cause said spring controlledpawl to. disengage said ratchet wheel and allow selecting impulses to betransmitted and to cause said spring controlled lock pawl to engage saidratchet Wheel and prevent the opposite movement of the said wheel, untilthe replacing of the receiver upon its switch allows the pivoted arm toreturn to normal position, the lock pawl disengaging and the positioningpawl engaging the ratchet wlicel.

4-. A rotatable call dial; selecting impulse mechanism! provided with aratchet wheel; a spring controlled arm, and a spring controlled pawlpivoted thereto, and in engagement with said ratchet wheel; all arran edto allow the dial to be manually moved orward or back and'retained inthe position where manually left, to facilitate the positioning thedial: eentrifugally operated governing and bra king means rotatablyconnected with said dial by a ratchet and pawl connection, whereby thereturn of the dial and impulse selecting mechanism, to normal position,is properly retarded.

In an electrical impulse transmitting device for the calling station ofan automatic telephone, a pair of ringing contact springs; a springoperated wheel, having a cam surface thereon which, after the seleetiugimpulses have been sent, momentarily closes contact between said springsbefore said wheel reaches normal position; for the purpose of sending tothe called station a single ringing signal.

(L In an electrical impulse transmitting device for the calling stationof an auto matic telephone, a pair of ringing contact springs in anautomatic ringing circuit;' a

spring operated wheel, having a cam surface thereon which, after theselecting-impulses have been sent, momentarily closes contact betweensaid springs before said wheel reaches normal position; for the purposeof sending to the called station a single ringing signal; a. manualringing circuit, a, contact spring in the said manual ringing cir' cult,that is contacted by said cam as it returns to and ,while it remains, innormal position. to render operative the manual ringing circuit when innormal position.

7. In an e leetrieal impulse transmitting device for the calling stationof an automatic telephone. a ringing circuit; a manually operatedringing button, to close said circuit; a spring operated wheel which hasa cam surface electrically grounded; a contact spring in said ringingcircuit, which engages sai cam surface only when said wheel is in normalposition, so that the ringing circuit is held open and cannot, bemanually closed, while the transmitting device is out of normalposition.

In testimony signature in the whereof I hereunto a tlix my presence oftwo witnesses. ALTON E. STEVENS.

\Vitne'sses:

CHARLES F. RICHARDSON, A. I. Cmwronn,

